Qiao, L., Ramanujan, R. V., Zhu, J. (2022). Optimized hot working parameters of Fe2.5Ni2.5CrAl multi-principal element alloys. Journal of Alloys and Compounds, 925, 166594. https://doi.org/10.1016/j.jallcom.2022.166594
Abstract:
The hot compressive deformation behavior of Co-free Fe2.5Ni2.5CrAl multi-principal element alloys (MPEAs) was investigated
in the temperature and strain rate ranges of 800-1100C and 0.001 s1 and 1 s1, respectively. Microstructural observations were
carried out by optical microscopy (OM) and electron backscatter di raction (EBSD). A constitutive model based flow-stress analysis
was carried out, the activation energy (Q) was obtained as 315.9 kJ/mol at steady state. The strain rate sensitivity (m), the power
dissipation (η), and instability parameter (ξ) were utilized to construct the processing maps. Power-law breakdown and unstable flow
occurred at the high strain rates at which strain hardening was pronounced. The optimal condition for successful hot working was
determined to be at strain rates in the range of 10−2–10−3 s−1 and a temperature range of 850 ~ 1020∘C. FEM simulations revealed
the strain and stress distribution during hot deformation and predicted instabilities during hot forming. The main deformation
mechanism was dislocation climb with a stress exponent n > 5. The Q value for plastic flow in the power-law creep regime was
calculated considering the e ect of lattice di usion of atoms and was in accordance with the measured Q value. Thus, our study
revealed the hot working characteristics and the optimum processing parameters for successful hot working of Fe2.5Ni2.5CrAl
MPEAs.
License type:
Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)
Funding Info:
This research / project is supported by the Agency for Science, Technology and Research - Structural Metal Alloys Programme
Grant Reference no. : A18B1b0061
This research / project is supported by the Agency for Science, Technology and Research - AME Programmatic Fund
Grant Reference no. : A1898b0043